The present invention relates to a beam-rotary lamp, especially to such a lamp that is set outdoors or on a roof of an emergency vehicle or other vehicle to give out an intermittent warning or decorative light.
There have been some problems or disadvantages in conventional beam-rotary lamp which has a reflector rotating around an electric lamp set at the center of the apparatus. In a kind of the device in which the motor power is conducted via reduction device comprising a gearing mechanism, the noise of gears is great and smooth conduction is apt to be disturbed by vibration of the apparatus or shocks given to the apparatus. Still more, if some teeth of the gears were broken, the apparatus would yield to impossibility of a further operation.
In order to solve said problems, an another kind of the apparatus comprising a limb-driving mechanism instead of the gearings has been proposed. A resilient plate to which the power of motor is conducted, in this case, is forcibly set in contact with the the support shaft of the reflector. However, it is difficult to adjust the resiliency to the optimum and is complicated in the structure causing consequently other troubles.
There has been an another disadvantage in those usual beam-rotary lamps. Namely, the lamp unit comprising the electric lamp and the power unit comprising the motor are voluminously arranged one upon another in a cylindrical housing.